<template>
  <div>
    <el-switch v-model="draggable" active-text="开启拖拽" inactive-text="关闭拖拽"></el-switch>
    <el-button v-if="draggable" @click="batchSave" type="success" size="mini">批量保存</el-button>
    <el-button @click="batchDelete" type="danger" size="mini">批量删除</el-button>
    <el-tree
      :data="menus"
      :props="defaultProps"
      @node-click="handleNodeClick"
      :expand-on-click-node="false"
      :show-checkbox="true"
      node-key="catId"
      :default-expanded-keys="expandedKey"
      :draggable="draggable"
      :allow-drop="allowDrop"
      @node-drop="handleDrop"
      ref="menuTree"
    >
      <span class="custom-tree-node" slot-scope="{ node, data }">
        <span>{{ node.label }}</span>
        <span>
          <!-- 1，2级菜单才显示appen按钮 -->
          <el-button
            v-if="node.level <= 2"
            type="text"
            size="mini"
            @click="() => append(data)"
          >
            Append
          </el-button>
          <el-button
            type="text"
            size="mini"
            @click="edit(data)"
          >
            editor
          </el-button>
          <!-- 节点没有子节点时才显示删除按钮 -->
          <el-button
            v-if="node.childNodes == 0"
            type="text"
            size="mini"
            @click="() => remove(node, data)"
          >
            Delete
          </el-button>
        </span>
      </span>
    </el-tree>

    <el-dialog :title="title" :visible.sync="dialogVisible" width="30%">
      <el-form :model="category">
        <el-form-item label="分类名称">
          <el-input v-model="category.name" autocomplete="off"></el-input>
        </el-form-item>
        <el-form-item label="图   标">
          <el-input v-model="category.icon" autocomplete="off"></el-input>
        </el-form-item>
        <el-form-item label="计量单位">
          <el-input v-model="category.productUnit" autocomplete="off"></el-input>
        </el-form-item>
      </el-form>
      <span slot="footer" class="dialog-footer">
        <el-button @click="dialogVisible = false">取 消</el-button>
        <el-button type="primary" @click="submitData()">确 定</el-button>
      </span>
    </el-dialog>
  </div>
</template>

<script>
export default {
  data() {
    return {
      pCid: [],
      draggable: false,
      updateNodes: [],
      maxLevel: 0,
      //对话框标题
      title: "",
      //对话框类型add,edit
      dialogType: "",
      menus: [],
      expandedKey: [],
      // 对话框
      dialogVisible: false,
      category: {name: "", parentCid: 0, catLevel: 0, showStatus: 1, sort: 0, catId: null, icon: '', productUnit: ''},
      defaultProps: {
        children: "children",
        label: "name"
      }
    };
  },
  methods: {
    handleNodeClick(data) {
    },
    getMenus() {
      this.$http({
        url: this.$http.adornUrl("/product/category/list/tree"),
        method: "get"
      }).then(({data}) => {
        console.log(data.data);
        this.menus = data.data;
      });
    },
    append(data) {
      console.log("append", data);
      //对话框类型
      this.dialogType = 'add';
      this.title = '添加';//对话框标题
      this.dialogVisible = true; //打开对话框
      this.category.parentCid = data.catId;
      this.category.catLevel = data.catLevel * 1 + 1; //防止catLevel值为字符串。
      //将edit回显的部分数据清空
      this.category.catId = null;
      this.category.name = "";
      this.category.icon = "";
      this.category.productUnit = "";
      this.category.sort = 0;
      this.category.showStatus = 1;
    },
    //添加三级分类
    addCategory() {
      console.log("提交的三级分类数据", this.category);
      this.$http({
        url: this.$http.adornUrl("/product/category/save"),
        method: "post",
        data: this.$http.adornData(this.category, false)
      }).then(({data}) => {
        this.$message({
          message: "菜单保存成功",
          type: "success"
        });
        //保存成功，关闭对话框
        this.dialogVisible = false;
        //删除成功，刷新重新获取菜单
        this.getMenus();
        //设置需要默认展开的菜单
        this.expandedKey = [this.category.parentCid];
      });
    },
    //删除
    remove(node, data) {
      var ids = [data.catId]; //拿到要删除的ID
      this.$confirm(`是否删除【${data.name}】菜单?`, "提示", {
        confirmButtonText: "确定",
        cancelButtonText: "取消",
        type: "warning"
      })
        .then(() => {
          this.$http({
            //向后端发送post请求，删除
            url: this.$http.adornUrl("/product/category/delete"),
            method: "post",
            data: this.$http.adornData(ids, false)
          }).then(({data}) => {
            this.$message({
              message: "菜单删除成功",
              type: "success"
            });
            //删除成功，刷新重新获取菜单
            this.getMenus();
            //设置需要默认展开的菜单
            this.expandedKey = [node.parent.data.catId];
          });
        })
        .catch(() => {
          this.$message({
            type: "info",
            message: "已取消删除"
          });
        });
    },
    //编辑
    edit(data) {
      console.log("要修改的数据", data);
      //对话框类型
      this.dialogType = 'edit';
      //框中内容回显内容 如果有多个人再同时修改该菜单时，会导致数据滞后
      //发送请求获取当前节点最新的数据
      this.$http({
        url: this.$http.adornUrl(`/product/category/info/${data.catId}`),
        method: "get",
        params: this.$http.adornParams({})
      }).then(({data}) => {
        //这里套了三层Object--->data--->data
        //请求成功
        console.log("要回显的数据", data)
        this.category.name = data.data.name;
        this.category.icon = data.data.icon;
        this.category.productUnit = data.data.productUnit;
        this.category.catId = data.data.catId;
        this.category.parentCid = data.data.parentCid;
      });
      /*      this.category.name = data.name;
            this.category.icon = data.icon;
            this.category.productUnit = data.productUnit;
            this.category.catId = data.catId;*/

      this.title = '修改';//对话框标题
      this.dialogVisible = true; //打开对话框
    },
    //编辑菜单
    editCategory() {
      //只修改这些字段数据
      var {catId, name, icon, productUnit} = this.category;
      console.log("修改的三级分类数据", this.category);
      this.$http({
        url: this.$http.adornUrl("/product/category/update"),
        method: "post",
        data: this.$http.adornData({catId, name, icon, productUnit}, false)
      }).then(({data}) => {
        this.$message({
          message: "菜单修改成功",
          type: "success"
        });
        //保存成功，关闭对话框
        this.dialogVisible = false;
        //删除成功，刷新重新获取菜单
        this.getMenus();
        //设置需要默认展开的菜单
        this.expandedKey = [this.category.parentCid];
      });
    },
    //确认提交方法
    submitData() {
      //判断对话框类型 add ? edit
      if (this.dialogType === 'add') {
        this.addCategory();
      }
      if (this.dialogType === 'edit') {
        this.editCategory();
      }
    },
    /**
     *
     * @param draggingNode 拖动节点
     * @param dropNode 目标节点
     * @param type 'prev'、'inner' 和 'next'，分别表示放置在目标节点前、插入至目标节点和放置在目标节点后
     * @returns {boolean} true：能拖动  false：不能
     */
    allowDrop(draggingNode, dropNode, type) {
      //1.被拖动的当前节点以及所在的父节点总层数不能大于3
      console.log("allowDrop", draggingNode, dropNode, type);

      this.countNodeLevel(draggingNode);
      // console.log("maxLevel", this.maxLevel);
      let deep = Math.abs(this.maxLevel - draggingNode.level) + 1;
      // console.log("深度", deep);

      if (type == "inner") {
        return (deep + dropNode.level) <= 3;
      } else {
        return (deep + dropNode.parent.level) <= 3;
      }
    },
    countNodeLevel(node) {
      //找到所有子节点，求出最大深度
      if (node.childNodes != null && node.childNodes.length > 0) {
        for (let i = 0; i < node.childNodes.length; i++) {
          if (node.childNodes[i].level > this.maxLevel) {
            this.maxLevel = node.childNodes[i].level;
          }
          this.countNodeLevel(node.childNodes[i]);
        }
      }
    },
    /**
     * 拖拽成功处理事件
     * @param draggingNode 被拖拽节点对应的 Node
     * @param dropNode 结束拖拽时最后进入的节点
     * @param dropType 被拖拽节点的放置位置 before、after、inner
     * @param ev 事件
     */
    handleDrop(draggingNode, dropNode, dropType, ev) {
      //1.当前节点最新的父节点id
      let pCid = 0;
      //兄弟节点，包含菜单顺序（数组）
      let siblings = null;
      if (dropType === "before" || dropType == "after") {
        pCid = dropNode.parent.data.catId == undefined ? 0 : dropNode.parent.data.catId;
        siblings = dropNode.parent.childNodes;
      } else {
        pCid = dropNode.data.catId;
        siblings = dropNode.childNodes;
      }
      this.pCid.push(pCid);

      //2、当前拖拽节点的最新顺序，
      for (let i = 0; i < siblings.length; i++) {
        if (siblings[i].data.catId == draggingNode.data.catId) {
          //如果遍历的是当前正在拖拽的节点
          let catLevel = draggingNode.level;
          if (siblings[i].level != draggingNode.level) {
            //当前节点的层级发生变化
            catLevel = siblings[i].level;
            //修改他子节点的层级
            this.updateChildNodeLevel(siblings[i]);
          }
          this.updateNodes.push({
            catId: siblings[i].data.catId,
            sort: i,
            parentCid: pCid,
            catLevel: catLevel
          });
        } else {
          this.updateNodes.push({catId: siblings[i].data.catId, sort: i});
        }
      }
      //3.当前拖拽节点的最新层级
      console.log("updateNodes", this.updateNodes);
    },
    updateChildNodeLevel(node) {
      if (node.childNodes.length > 0) {
        for (let i = 0; i < node.childNodes.length; i++) {
          var cNode = node.childNodes[i].data;
          this.updateNodes.push({
            catId: cNode.catId,
            catLevel: node.childNodes[i].level
          });
          this.updateChildNodeLevel(node.childNodes[i]);
        }
      }
    },
    batchSave() {
      this.$http({
        url: this.$http.adornUrl("/product/category/update/sort"),
        method: "post",
        data: this.$http.adornData(this.updateNodes, false)
      })
        .then(({data}) => {
          this.$message({
            message: "菜单顺序等修改成功",
            type: "success"
          });
          //刷新出新的菜单
          this.getMenus();
          //设置需要默认展开的菜单
          this.expandedKey = this.pCid;
          this.updateNodes = [];
          this.maxLevel = 0;
          // this.pCid = 0;
        })
        .catch(() => {
        });
    },
    batchDelete() {
      let catIds = [];
      let checkedNodes = this.$refs.menuTree.getCheckedNodes();
      // console.log("被选中的元素", checkedNodes);
      for (let i = 0; i < checkedNodes.length; i++) {
        catIds.push(checkedNodes[i].catId);
      }
      this.$confirm(`是否批量删除【${catIds}】菜单?`, "提示", {
        confirmButtonText: "确定",
        cancelButtonText: "取消",
        type: "warning"
      })
        .then(() => {
          this.$http({
            url: this.$http.adornUrl("/product/category/delete"),
            method: "post",
            data: this.$http.adornData(catIds, false)
          }).then(({data}) => {
            this.$message({
              message: "菜单批量删除成功",
              type: "success"
            });
            this.getMenus();
          });
        })
        .catch(() => {
        });
    },
  },
  created() {
    this.getMenus();
  }
};
</script>

<style></style>
